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UK Civil Aviation Regulations

These are published by the CAA on our UK Regulations pages. EU Regulations and EASA Access Guides published by EASA no longer apply in the UK. Our website and publications are being reviewed to update all references. Any references to EU law and EASA Access guides should be disregarded and where applicable the equivalent UK versions referred to instead.



Fixed and mobile offshore / platform installations require a valid ANO approval and radio licence for Aeronautical VHF and Non-Directional Radio Beacons (NDB). Radio licensing is now managed by Ofcom.

Please see our separate radio licensing guidance for details.

International operators

While Ofcom dictates rules on radio licence requirements for international vessels entering UK waters, the CAA still requires all ground stations and platforms to hold valid ANO approvals for all ground station radio equipment. Operators should contact the CAA approvals team to gain approval for their equipment.

Further details on the approval and licensing of ground radio stations can be found in the AIP, GEN 3.4 section 4.2.

For further information please contact Approvals.RCS@caa.co.uk

Channel assignment

Typically, channels are assigned as ‘common’ or ‘dedicated’ for offshore operators. Most operators, including mobile vessels utilise common channels. These channels are listed in the AIP under section ENR 1.6 and are illustrated in associated charts, ENR 6-29 through to ENR 6-31. Some fixed vessels utilise ‘dedicated’ channels which are specific to an installation or a collection of. These are not published in the AIP and operators are expected to ensure they are utilising the correct 8.33kHz channels. Channels may be published on the helideck plates hosted by the Helideck Certification Agency (HCA).

The CAA is aware that some HCA plates hosted on the HCA website are not yet up to date and contain historic 25kHz frequencies. All operators should be utilising 8.33kHz channels, this includes all dedicated and common channel assignments. The CAA is working with the HCA to rectify this as soon as possible.

8.33 kHz channels

All offshore ground stations should now be utilising 8.33kHz channels, which were converted in late 2018. 8.33 or 25kHz channels can be identified by the last three digits of the channel after the decimal place.

25 kHz Channels ending in x00, x25, x50, x75 can easily be converted to 8.33kHz channels by adding 5 to the last digit, e.g. x05, x30, x55, x80. A detailed conversion table is published in CAP 1580 (see table 1).

It is also noted that due to the format of radio licensing paper work provided by Ofcom the complete channel reference may not appear and could incorrectly be read as a 25kHz frequency. If you need assistance identifying the correct channel, please contact the CAA spectrum team or refer to the AIP.

Further details regarding 8.33

The Spectrum team can be contacted by email: spectrum@caa.co.uk

ANO Approvals

All ground stations (including visiting international vessels) require an ANO approval for any aeronautical radio equipment used. This includes handhelds units. It is the responsibility of the licence holder to ensure they have the relevant ANO approval which covers the equipment currently installed. An ANO approval is required by law and is a condition of the wireless telegraphy licence of all ground operators including offshore platforms. It is the operator’s responsibility to ensure they hold a valid ANO approval for their equipment and to ensure all details are correct.

In 2018 the CAA carried out an audit on all offshore ANO approvals to ensure that all equipment was suitable for use on 8.33 kHz channels. As a result all ANO approvals were re-issued as a temporary or new permanent approval on or after the 21st December 2018. If you hold an ANO approval dated before this date (and hold a current WT Act Radio Licence issued by Ofcom), you should contact the CAA to request a revised approval to ensure your equipment is suitable for use on 8.33kHz channels.

UK operators who do not hold a valid WT Act Radio Licence or are unsure should contact Ofcom as soon as possible.
If you need assistance identifying that your equipment is suitable or do not hold an ANO dated after December 2018 please contact the CAA approvals team. It is a legal requirement to hold an ANO approval from the CAA which reflects the current equipment being utilised.

The CNS Approvals team can be contacted by email: Approvals.RCS@caa.co.uk.

Risk of interference

It is important all operators utilise 8.33kHz channels and that both ground stations and aircraft ensure their equipment is set correctly to utilise 8.33kHz channel spacing. Further information is provided in CAP 1580. Failure to ensure equipment is configured correctly, to the correct 8.33kHz channel could result in communication difficulties between ground stations and aircraft, and an increased risk of interference from adjacent channels.

NDB operations

Channelisation for Non-Directional Radio Beacons has not changed, but operators should still ensure they hold a correct ANO approval for their equipment. Please note that Aeronautical NDBs may need to be able to tune over the frequency range of 435kHz to 949kHz depending on the area of operation.